APX811-31U

Microprocessor Supervisory Circuit

The APX811-31U is a microprocessor supervisory circuit from Diodes Incorporated. View the full APX811-31U datasheet below including key specifications, electrical characteristics, absolute maximum ratings.

APX811-31U shares its datasheet with APX811-40UG-7, whose page lists every part number it covers.

Official APX811-31U datasheet (PDF) — the source this page was extracted from.

Manufacturer

Diodes Incorporated

APX811-31U Key Specifications

Parameter	Value
Case/Package	SOT-143
DigiKey Programmable	Not Verified
Max Operating Temperature	85 °C
Max Power Dissipation	320 mW
Max Reset Threshold Voltage	4.06 V
Max Supply Voltage	5.5 V
Min Operating Temperature	-40 °C
Min Reset Threshold Voltage	3.94 V
Min Supply Voltage	1.1 V
Mount	Surface Mount
Mounting Type	Surface Mount
Number of Channels	1
Number of Elements	1
Number of Pins	4
Number of Voltages Monitored	1
Number of Voltages Monitored	1
Operating Temperature	-40°C ~ 85°C (TA)
Output	Push-Pull, Totem Pole
Package / Case	TO-253-4, TO-253AA
Power Dissipation	320 mW
Radiation Hardening	No
Reset	Active Low
Reset	Active Low
Reset Timeout	140 ms
Reset Timeout	140ms Minimum
RoHS	Compliant
Supplier Device Package	SOT-143
Threshold Voltage	4 V
Type	Simple Reset/Power-On Reset
Type	Simple Reset/Power-On Reset
Voltage - Threshold	4V
Watchdog Timer	No

APX811-31U Overview

Part: APX811-40UG-7 — Diodes Incorporated

Type: Microprocessor Supervisory Circuit

Description: Precision power supply monitor for 2.5V/3.0V/3.3V/5.0V systems with a power-on reset generator, fixed 200ms delay time, and manual reset input, available in push-pull active low (APX811) or active high (APX812) output configurations.

Operating Conditions:

Supply voltage: 1.1–5.5 V
Operating ambient temperature: -40 to 85 °C
Input voltage: 0 to (VCC+0.3) V

Absolute Maximum Ratings:

Max supply voltage: 7 V
Max input current, Vcc: 20 mA
Max output current: 20 mA
Max power dissipation: 320 mW

Key Specs:

Supply Current (ICC): 30 μA (Typ), 40 μA (Max) at Vth + 0.2V
Reset threshold (Vth): 3.94 V (Min), 4.0 V (Typ), 4.06 V (Max) at TA=25°C (for -40U variant)
RESET Output Voltage Low (VOL): 0.3 V (Max) at VCC = Vth -0.2, ISINK = 1.2mA (APX811)
RESET Output Voltage High (VOH): 0.8VCC (Min) at VCC > Vth +0.2, ISOURCE = 500μA (APX811)
Power-on reset delay time (td): 140 ms (Min), 200 ms (Typ), 280 ms (Max)
MR to RESET propagation delay (tPHL/tPLH): 0.1 μs (Max)
VCC to RESET propagation delay (tPHL/tPLH): 25 μs (Max)

Features:

Precision Monitor of (2.5V/3.0V/3.3V/5.0V) power supply voltage
Full specified over temperature
Available in four output configuration
Manual reset input
Push-pull RESET Active low (APX811)
Push-pull RESET Active high (APX812)
Power-on reset generator with fixed delay time 200ms
SOT143: Available in 'Green' Molding Compound (No Br, Sb)
Lead Free Finish/RoHS Compliant

Applications:

Computers
Controllers
Intelligent Instruments
Portable/Battery powered Equipment
Critical uP and UC power Monitoring
Automotive

Package:

SOT143

APX811-31U Applications

Computers
Controllers
Intelligent Instruments
Portable/Battery powered Equipment
Critical uP and UC power Monitoring
Automotive

APX811-31U Pin Configuration

APX811-31U Electrical Characteristics

TA= -40 to 85 o C unless otherwise note. Typical values are at TA=+25 o C.

Symbol	Parameter	Test Conditions	Min	Typ.	Max	Unit
V CC	V CC Range		1.0		5.5	V
I CC	Supply Current	V th + 0.2V		30	40	μA
			2.22	2.25	2.28	V
			2.59	2.63	2.67	V
			2.89	2.93	2.98	V
V th	Reset threshold	T A =25 o C.	3.03	3.08	3.13	V
			3.94	4	4.06	V
			4.31	4.38	4.45	V
			4.56	4.63	4.7	V
t s	Set-up Time	V CC = V th to (V th - 100mV)		20		μs
	RESET Output Voltage Low	V CC = V th -0.2, I SINK = 1.2mA			0.3	V
V OL	(APX811)	V CC = V th -0.2, I SINK = 3.2mA V CC > 1.0V, I SINK = 50μA			0.4 0.3
V OH	RESET Output Voltage-High	V CC > V th +0.2, I SOURCE = 500μA	0.8V CC			V
	(APX811)	V CC > V th +0.2, I SOURCE = 800μA	V CC -1.5			V
V OL	RESET Output Voltage-Low	V CC = V th +0.2, I SINK = 1.2mA			0.3	V
	(APX812)	V CC = V th +0.2, I SINK = 3.2mA			0.4	V
V OH	RESET Output Voltage-High (APX812)	1.8V < V CC < V th -0.2, I SOURCE = 150μA	0.8 V CC			V
θ JA	Thermal Resistance Junction-to-Ambient	SOT143 (Note 3)		240		o C/W
θ JC	Thermal Resistance Junction-to-Case	SOT143 (Note 3)		71		o C/W

Notes: 3. Test condition for SOT143: Device mounted on FR-4 substrate, 1"*1", 2oz, copper, single-sided, PC boards.

APX811-31U Absolute Maximum Ratings

Symbol	Parameter	Rating	Unit
ESD HBM	Human Body Model ESD protection	3	kV
ESD MM	Machine Model ESD Protection	500	V
V CC	Supply voltage	-0.3~7	V
V RESET	RESET	-0.3 to (Vcc+0.3)	V
I CC	Input Current, Vcc	20	mA
I O	Output current	20	mA
P D	Power dissipation	320	mW

Recommended Operating Conditions

Symbol	Parameter	Min	Max	Unit
V CC	Supply Voltage	1.1	5.5	V
V IN	Input Voltage	0	(V CC +0.3)	V
T A	Operating Ambient Temperature	-40	85	o C

OCTOBER 2009

APX811-31U Typical Application

The APX811/812 are used for microprocessor supervisory circuit to monitor the power supplies in These circuit perform a single function: they assert a reset signal whenever the Vcc supply voltage declines below a preset threshold, keeping it asserted for at least 240ms after Vcc has risen above the reset threshold. Reset thresholds suitable for operation with a variety of supply voltages are available. The APX811/812 have push-pull outputs.

The APX811 has an active low RESET output, while the APX812 has an active high RESET output.

The APX811/812 devices incorporate a manual reset input, MR . A low level at MR causes RESET to become active.

The APX811/2 are targeted at 2.5V, 3V, 3.3V and 5V powered systems and are available with different threshold voltages to meet the exact needs of the system. They are available in the space saving SOT143 package and operate over the whole industrial temperature range, -40 to 85°C.

Variants on the same datasheet

These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.

Part Number	Manufacturer	Package
APX811	Diodes Incorporated	SOT143
APX811-23U	Diodes Incorporated	SOT143
APX811-26U	Diodes Incorporated	SOT143
APX811-29U	Diodes Incorporated	SOT143
APX811-40U	Diodes Incorporated	SOT143
APX811-40UG-7	Diodes Incorporated	TO-253-4, TO-253AA
APX811-44U	Diodes Incorporated	SOT143
APX811-46U	Diodes Incorporated	SOT143
APX811/2	Diodes Incorporated	SOT143
APX811/812	Diodes Incorporated	SOT143

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